-92 naturally occurring elements
-Elements with the atomic number greater then 92 do not exist in nature
-Elements in groups 1A through 8A are called representative elements because as a group , they display a wide range of physical and chemical properties. Example- 1A through 8A include metals and nonmentals; highly reactive elements and some that hardly react at all; and elements that are solids, liquids, and gases at room temperature
Some period 2 elements do not behave as predicted by their locations on the table. The lightest element in a group is the least representative; these elements have more in common with the period 3 element in the next group than with the period 3 element in their own group.
Alkaline Metals
-Medieval alchemists classified solids that did not melt in their fires as “earths”-Group 2A elements form compounds with oxygen, called oxides.
o Qualify as “earths” by this definition
-Beryllium oxide
+produce alkaline solutions when they react with water.
-Alkaline earth metals:
1. Shiny solids that are harder than alkali metals.
2. Less reactive than alkali metals
3. Lose their two valence electrons to form ions with a 2+ charge. [Reaction with water reveals the relative reactivity of the alkaline earth metals]
-Magnesium will react in hot water.
-Beryllium does not appear to react with water.
Beryllium
-Lightest member of Group 2A.
-Found combined with aluminum, silicon, and oxygen in material called beryl.
-Beryllium is used to moderate neutrons in nuclear reactors.
Calcium
-Essential element for humans [bones & teeth]
-Found widely in nature, mainly combined with carbon and oxygen.
-Used in antacid tablets and as an abrasive in toothpaste.
-Abrasive = hard material used to polish, smooth, or grind a softer material.
-When decomposes, forms an oxide of calcium called lime.
-Lime is one of the most important industrial compounds.
-Lime plays a role in the manufacture of steel, paper, and glass.
Magnesium
-Abundant element that can be formed into almost any shape.
-Alloys of magnesium with aluminum and zinc are much lighter than steel but equally
strong.
-Oxide of magnesium has such a high melting point that is used to line furnaces.
- Plants cannot function without a supply of magnesium.
- Due to chlorophyll molecule contains a magnesium ion.
7.2
Aluminum-Aluminum is the most abundant metal and the 3rd most abundant element in the Earth’s crust. Usually occurs with oxygen or silicon. Removing aluminum from its ore is very expensive so it is cost effective to recycle the products into cans.
Aluminum oxide is the major compound in bauxite and is used as an abrasive to strengthen ceramics and resistant fabrics. Many gems, including ruby and sapphire, are crystals of aluminum.
Allotropes
Allotropes are forms of an element in the same physical state—solid, liquid, or gas—have different structures and properties. Since diamond and graphite are solids made of carbon, they are allotropes. Silicon
Silicon is the second most abundant element in the Earth’s crust. The first is oxygen. Silicon is also used in computer chips and solar cells. Both can be melted and rapidly cooled to form glass Carbon
Because a carbon atom can join with up four other carbon atoms, carbon forms millions of organic compounds
Carbon is one of the most important elements on earth. Most substances that control what happens in cell have carbon. The branches that studies carbon is are organic chemistry and inorganic chemistry.
P-block elements include metals, metalloids, nonmetals, and inert gases.
S-block metals are slight in comparison to the range of properties found among the p-block elements. P-block elements are metals, metalloids, nonmetals, and inert gases.
Some are solids and some are gases at room temperature.
Even individually p-block elements display a greater range of properties.
For example, many form more than one type of ion. As you might expect, the explanation for this property lies with the electron configurations.
Graphite and diamond are allotropes of carbon.
· Diamond and graphite contain only carbon atoms, they both display different properties.
· Graphite is one of the softest known materials; diamond is one of the hardest.
These different forms of the same element are examples of allotropes. Allotropes are forms of an element in the same physical state-solid, liquid, or gas-that has different structures and properties.
· Because diamond and graphite are both solids made of carbon, they are allotropes.
Lead used to be used in pipes, paint, and gasoline until people realized that lead was toxic and could lead to lead poisoning.
Lead was first used because of it low melting point, but the analysis of ancient skeletons showed a high content of lead left over in the bones.
Lead is especially harmful to preschool children, it used to be used in paint, so now landlords cannot rent out to family with young children until the lead paint is removed.
Currently the only major use of lead is in storage batteries for automobiles.
NITROGEN
Nitrogen Gas is colorless, odorless, and relatively unreactive.
About 78% of earth’s atmosphere is Nitrogen.
A major industrial use of hydrogen is to produce Nitrogen ammonia. This is a colorless gas with an irritating odor. It is used in many cleaning products.
Liquid ammonia can be a source of nitrogen for many plants. It is stored under pressure and pumped directly into the soil.
About 25% of ammonia is converted into nitric acid, which then is used to create explosives, dyes, and solid fertilizers.
Some nitrogen compounds are very unstable including TNT and nitroglycerine.
Phosphorus
· White phosphorus bursts into flames in air and must be stored in water.
· Red phosphorus is less reactive and is used on the striking surface of matchboxes.
· Black phosphorus is produced when either red or white phosphorus is heated under high pressure.
Most phosphorus is used to make phosphoric acid which is converted into phosphorus compounds.
Phosphate compounds have many uses. (found in processed cheeses, laxatives, and baking powders, used as flame-retardant coating for fabrics, grease remover in cleaning products, and is often found in fertilizers)
Fertilizers and cleaning products that contain phosphates can be harmful to the environment.
Phosphate ions from fertilized fields can reach lakes and cause a build up of algae. The algae builds up on the surface on the lake and prevents light from reaching the algae below the surface which then does not get enough light for photosynthesis and will die. There will then not be enough oxygen for other organisms to survive.
Sulfur
When sulfur is burned in air, it reacts with oxygen to from sulfur dioxide.
Sulfur Dioxide is used to preserve fruit and as an antibacterial agent.
When sulfur dioxide is released into the atmosphere it reacts with water vapor and forms one of the acids in acid rain.
More than 90% of sulfur dioxide that is produced is used to make sulfuric acid. About half of this sulfuric acid is used to make fertilizers.
Some places deep in the ocean that can’t rely on photosynthesis have to start with hydrogen sulfide. The hydrogen sulfide comes out of vents. Bacteria that live near the vents where the hydrogen sulfide comes out uses it as an energy source.
Volcanoes also release hydrogen sulfide into the atmosphere.
HALOGENS
· They are always found combined with other elements in nature.
· Only have 7 valence electrons so they want to either share or gain one electron to attain a stable configuration
.· FLUORINE
o Greatest tendency to attract electrons.
o Used to lower melting points
o Use in toothpaste, drinking water, and a non-stick coating for cookware
NOBLE GASES
· Colorless and unreactive
· Very stable
· HELIUM
o Lightest noble gas
o Use in blimps, airships, and balloons
o Also used in diving tanks for divers to prevent a condition called the bends
o Coolant for superconducting magnets
· NEON
o Electrons in the atoms are excited which cause a color to be emitted
o Neon is not the only element used in neon lights because different elements create different colors when excited.
7.3 Properties of d-block and f-block Elements
The d-block transition metals and f-block inner transition metals are more similar across a period than are the s-block and p-block elements. The d-block and f-block are more similar than the s- and p -blocks because they have more similar fundamental properties.
Transition metals share properties such as electrical conductivity, luster and malleability with other metals.
The more unpaired electrons in an element’s d sublevel, the harder the transition metal and the higher its’ melting and boiling points become.
As you move horizontally (left to right) across a period, elements become much harder and require more heat for melting and boiling, that is until one reaches chromium.
Chromium has 5d electrons and one unpaired s electron. It is the hardest, and has a high melting point. Elements such as iron and cobalt form pairs of d electrons and thus (after Chromium) the melting points and hardness of elements decrease from left to right.
Transition metals can lose 2 electrons and form ions with a 2+ charge or higher.
Metal ions (with partially filled d sublevels) have electrons that can absorb visible light with specific wavelengths forming different colors.
7.3 2nd Half Ferromagnetism: The strong attraction of a substance to a magnetic field
Ferromagnetic Metals:
-Iron
-Cobalt
-Nickel
Their ions are aligned in the direction of the magnetic field
When the field is removed:
-the ions stay aligned
-the metal continues to act as a magnet
Each ion in a ferromagnetic metal acts as a magnet (First Picture). If all ions are aligned in the same direction, they can form a permanent magnet (Second Picture). Transition Metals:
Have a variety of uses
Strategic materials – the economy and military depend of the materials
Play a vital role in the economy of many countries
Many transition metals are found in alloys
Your body needs a few transition elements in large amounts to function
It also needs trace amounts of other elements
Many trace elements are transition elements
Inner Transition Metals- F- Block:
*Period 6- Lanthanides means “hard to get at” in Greek.
Silvery metals with high melting points
Found mixed in nature
Very hard to separate
*Period 7- Actinides
Radioactive elements (emit radiation)
Only 3 actinides exist in nature, the rest are synthetic
Transuranium elements= elements with an atomic number greater than 92
Created in particle accelerators or nuclear reactors
Decay quickly
One exception- Plutonium 239- can remain radioactive for thousands of years
-Elements with the atomic number greater then 92 do not exist in nature
-Elements in groups 1A through 8A are called representative elements because as a group , they display a wide range of physical and chemical properties. Example- 1A through 8A include metals and nonmentals; highly reactive elements and some that hardly react at all; and elements that are solids, liquids, and gases at room temperature
Some period 2 elements do not behave as predicted by their locations on the table. The lightest element in a group is the least representative; these elements have more in common with the period 3 element in the next group than with the period 3 element in their own group.
Alkaline Metals
-Medieval alchemists classified solids that did not melt in their fires as “earths”-Group 2A elements form compounds with oxygen, called oxides.
o Qualify as “earths” by this definition
-Beryllium oxide
+produce alkaline solutions when they react with water.
-Alkaline earth metals:
1. Shiny solids that are harder than alkali metals.
2. Less reactive than alkali metals
3. Lose their two valence electrons to form ions with a 2+ charge.
[Reaction with water reveals the relative reactivity of the alkaline earth metals]
-Magnesium will react in hot water.
-Beryllium does not appear to react with water.
Beryllium
-Lightest member of Group 2A.
-Found combined with aluminum, silicon, and oxygen in material called beryl.
-Beryllium is used to moderate neutrons in nuclear reactors.
Calcium
-Essential element for humans [bones & teeth]
-Found widely in nature, mainly combined with carbon and oxygen.
-Used in antacid tablets and as an abrasive in toothpaste.
-Abrasive = hard material used to polish, smooth, or grind a softer material.
-When decomposes, forms an oxide of calcium called lime.
-Lime is one of the most important industrial compounds.
-Lime plays a role in the manufacture of steel, paper, and glass.
Magnesium
-Abundant element that can be formed into almost any shape.
-Alloys of magnesium with aluminum and zinc are much lighter than steel but equally
strong.
-Oxide of magnesium has such a high melting point that is used to line furnaces.
- Plants cannot function without a supply of magnesium.
- Due to chlorophyll molecule contains a magnesium ion.
7.2
Aluminum-Aluminum is the most abundant metal and the 3rd most abundant element in the Earth’s crust. Usually occurs with oxygen or silicon. Removing aluminum from its ore is very expensive so it is cost effective to recycle the products into cans.
Aluminum oxide is the major compound in bauxite and is used as an abrasive to strengthen ceramics and resistant fabrics. Many gems, including ruby and sapphire, are crystals of aluminum.
Allotropes
Allotropes are forms of an element in the same physical state—solid, liquid, or gas—have different structures and properties. Since diamond and graphite are solids made of carbon, they are allotropes.
Silicon
Silicon is the second most abundant element in the Earth’s crust. The first is oxygen. Silicon is also used in computer chips and solar cells. Both can be melted and rapidly cooled to form glass
Carbon
Because a carbon atom can join with up four other carbon atoms, carbon forms millions of organic compounds
Carbon is one of the most important elements on earth. Most substances that control what happens in cell have carbon. The branches that studies carbon is are organic chemistry and inorganic chemistry.
P-block elements include metals, metalloids, nonmetals, and inert gases.
S-block metals are slight in comparison to the range of properties found among the p-block elements. P-block elements are metals, metalloids, nonmetals, and inert gases.
- Some are solids and some are gases at room temperature.
- Even individually p-block elements display a greater range of properties.
- For example, many form more than one type of ion. As you might expect, the explanation for this property lies with the electron configurations.
Graphite and diamond are allotropes of carbon.· Diamond and graphite contain only carbon atoms, they both display different properties.
· Graphite is one of the softest known materials; diamond is one of the hardest.
These different forms of the same element are examples of allotropes. Allotropes are forms of an element in the same physical state-solid, liquid, or gas-that has different structures and properties.
· Because diamond and graphite are both solids made of carbon, they are allotropes.
7.2 Properties of p-block second half
LEAD
- Lead used to be used in pipes, paint, and gasoline until people realized that lead was toxic and could lead to lead poisoning.
- Lead was first used because of it low melting point, but the analysis of ancient skeletons showed a high content of lead left over in the bones.
- Lead is especially harmful to preschool children, it used to be used in paint, so now landlords cannot rent out to family with young children until the lead paint is removed.
- Currently the only major use of lead is in storage batteries for automobiles.
NITROGEN- Nitrogen Gas is colorless, odorless, and relatively unreactive.
- About 78% of earth’s atmosphere is Nitrogen.
- A major industrial use of hydrogen is to produce Nitrogen ammonia. This is a colorless gas with an irritating odor. It is used in many cleaning products.
- Liquid ammonia can be a source of nitrogen for many plants. It is stored under pressure and pumped directly into the soil.
- About 25% of ammonia is converted into nitric acid, which then is used to create explosives, dyes, and solid fertilizers.
- Some nitrogen compounds are very unstable including TNT and nitroglycerine.
Phosphorus· White phosphorus bursts into flames in air and must be stored in water.
· Red phosphorus is less reactive and is used on the striking surface of matchboxes.
· Black phosphorus is produced when either red or white phosphorus is heated under high pressure.
- Most phosphorus is used to make phosphoric acid which is converted into phosphorus compounds.
- Phosphate compounds have many uses. (found in processed cheeses, laxatives, and baking powders, used as flame-retardant coating for fabrics, grease remover in cleaning products, and is often found in fertilizers)
- Fertilizers and cleaning products that contain phosphates can be harmful to the environment.
- Phosphate ions from fertilized fields can reach lakes and cause a build up of algae. The algae builds up on the surface on the lake and prevents light from reaching the algae below the surface which then does not get enough light for photosynthesis and will die. There will then not be enough oxygen for other organisms to survive.
SulfurHALOGENS
· They are always found combined with other elements in nature.
· Only have 7 valence electrons so they want to either share or gain one electron to attain a stable configuration
.· FLUORINE
o Greatest tendency to attract electrons.
o Used to lower melting points
o Use in toothpaste, drinking water, and a non-stick coating for cookware
NOBLE GASES
· Colorless and unreactive
· Very stable
· HELIUM
o Lightest noble gas
o Use in blimps, airships, and balloons
o Also used in diving tanks for divers to prevent a condition called the bends
o Coolant for superconducting magnets
· NEON
o Electrons in the atoms are excited which cause a color to be emitted
o Neon is not the only element used in neon lights because different elements create different colors when excited.
7.3 Properties of d-block and f-block Elements
7.3 2nd Half
Ferromagnetism: The strong attraction of a substance to a magnetic field
- Ferromagnetic Metals:
-Iron-Cobalt
-Nickel
- Their ions are aligned in the direction of the magnetic field
- When the field is removed:
-the ions stay aligned-the metal continues to act as a magnet
Each ion in a ferromagnetic metal acts as a magnet (First Picture). If all ions are aligned in the same direction, they can form a permanent magnet (Second Picture).
Transition Metals:
- Have a variety of uses
- Strategic materials – the economy and military depend of the materials
- Play a vital role in the economy of many countries
- Many transition metals are found in alloys
- Your body needs a few transition elements in large amounts to function
- It also needs trace amounts of other elements
- Many trace elements are transition elements
Inner Transition Metals- F- Block:*Period 6- Lanthanides means “hard to get at” in Greek.
- Silvery metals with high melting points
- Found mixed in nature
- Very hard to separate
*Period 7- Actinides